1. Field of the Invention
The invention relates to a sunshade for a motor vehicle roof with a shade screen which can be wound onto a winding rod and which is located underneath the roof; the opposing side edges of the shade being movably guided in the direction of shade motion on guide rails and being held in the transverse direction with pre-tensioning of the shade.
2. Description of the Related Art
Published German Patent Application DE 197 39 919 A1 discloses one such sunshade in which edge stiffening is formed on the side edges of the shade, for example, in the form of a U-shaped, injected-on plastic edge which is movably held in a bent guide area of the guide rail and due to its stiffness and greater thickness in the transverse direction cannot slide out of the guide rail. When the shade screen is wound onto the winding shaft, however, the thickened edge is disadvantageous, since a nonuniform winding diameter is formed over the length of the winding shaft.
U.S. Pat. No. 6,161,893 discloses a sunshade for motor vehicle roofs which has a shade with several bars which are guided in lateral guide rails. When the shade is unwound from the winding shaft, the bars are arched by the two guide rails in the vertical direction, so that the shade is held in tension. However, when the shade is wound up, the bars greatly increase the winding diameter and the bars cause a nonuniform winding process.